fix format

src/http/ngx_http_request_body.c

diff --git a/src/http/ngx_http_request_body.c b/src/http/ngx_http_request_body.c
index 16d60a0..bfdc8e4 100644
--- a/src/http/ngx_http_request_body.c
+++ b/src/http/ngx_http_request_body.c
@@ -317,7 +317,7 @@
         }
 
         ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
-                       "http client request body rest %uz", rb->rest);
+                       "http client request body rest %O", rb->rest);
 
         if (rb->rest == 0) {
             break;